The present invention is directed to sterilization wrap materials. More particularly, the present invention is directed to multi-plied materials made from individual sheets which are fused together so as to be suitable for use as a sterilization wrap for wrapping surgical instruments and supplies for sterilization and storage in conjunction with surgical procedures and for other applications such as packaging items for bone marrow units.
Personnel in the Central Service Room (CSR) or the Sterile Processing Department (SPD) of hospitals are commonly charged with the responsibility of packaging surgical supplies to ensure that the sterility of the packaged contents are maintained all the way from sterilization to the point of reuse. Several activities are involved in the task of sterile supply delivery to the operating room and other units.
Much of the surgical instruments and supplies used in the operating room are reusable. These supplies typically include such things as clamps, scalpel blade handles, retractors, forceps, scissors, surgeons towels, basins and the like. All of these supplies must be collected after each procedure and sterilized before they can be used again in another procedure. To this end, the supplies are placed in stainless steel instrument trays, and soft goods such as surgeons towels, drapes, and gowns are prepared for packaging. Then, the trays and package contents are each generally wrapped with two sheets of material commonly referred to as sterilization wrap.
The sterilization wrap is usually a woven or nonwoven material which when wrapped around the tray or package contents in a certain prescribed manner will permit the entry of sterilizing vapor/gas or other medium to sterilize the contents of the tray while denying the ingress of contaminants such as bacteria and other infectious causing materials or their vehicles after sterilization. Generally, the two primary means for sterilizing instruments are autoclaving with steam and ethylene oxide sterilization.
Using a wrapped tray as an example, once the wrapped tray and its contents have been sterilized, the wrapped tray is transported to the point of use, typically an operating room, or is stored until it is ready to be used. During storage and transfer to the operating room, the wrapped tray may be handled several different times. Each time the wrapped package is handled, there is a potential that the sterile nature of the package contents can be compromised. The two most common ways the wrapped package can be compromised are a tear or other breach of the wrapping material, and wetness or foreign materials identified on the outer wrapper, which would warrant a premature unwrapping.
In order to promote and maintain the sterility of the packaged contents, the Association of Operating Room Nurses (AORN) has developed certain recommended practices for the wrapping and handling of in-hospital processed packages. It is common practice among many hospitals as recommended by the AORN to xe2x80x9cdouble wrapxe2x80x9d in-hospital processed packages. A primary method of double wrapping is xe2x80x9csequentialxe2x80x9d in nature in that the package contents are first wrapped by one sheet of sterilization wrap and then wrapped again by another sheet of sterilization wrap. Another method of double wrapping is xe2x80x9csimultaneousxe2x80x9d in nature in that the package contents are wrapped by two sheets of sterilization wrap at the same time. That is, two sheets of sterilization wrap are aligned one on top of the other, and the item to be wrapped is placed on top of the two sheets, then the item is wrapped by both sheets of material at the same time.
Studies have been used to track packages from initial wrapping, all the way through sterilization, storage, handling, transfer, unwrapping and ultimate reuse. These studies indicate that the frequency of compromising wrapped items due to tears or holes has been reduced because of improved handling and storage techniques and because of improved sterilization packaging products. One of the main thrusts behind such efforts has been economics. Every time a sterile package is compromised, it must be taken out of circulation, unwrapped, rewrapped, and resterilized before it can properly be reused. This wastes time and money.
While the frequency of compromising wrappers has been reduced thus resulting in the saving of time and money, the use of simultaneous wrapping techniques would further increase the time savings in wrapping and opening packages and thus result in a still greater cost savings. Simultaneous wrapping takes less time than sequential wrapping and recent research in hospitals has shown simultaneous wrapping to be just as effective as sequential wrapping in maintaining sterility absent a breach in the wrap which is generally independent of the manner of wrapping.
Even though the hospital staff may desire to simultaneously wrap instead of sequentially wrap, the time it takes to set up the outer and inner sheet wrappers and the awkwardness of manipulating loose wrappers during simultaneous wrapping can offset the time savings hoped to be achieved when attempting to move away from sequential wrapping. Consequently, if a product existed which provided the appropriate inner and outer sheet combinations and eliminated the awkwardness of keeping the two sheets together during the package wrapping and opening processes, then a simultaneous packaging system would deliver the benefits desired including time savings and targeted engineered inner and outer sheet performance.
In conjunction with the manner in which the packages are wrapped, the material used for wrapping is also important. As mentioned above, the two most common wrapping materials are woven materials such as cloth (cotton/polyester), nonwoven materials such as KIMGUARD(copyright) Sterile-Wrap (polypropylene) from Kimberly-Clark Corporation of Neenah Wis. and Bio-shield CSR Wrap (wood pulp/polyester) from Baxter Healthcare Corporation of Deerfield, Ill.. One version of the Baxter sterilization wrap is a product called DualWrap(copyright) Sterilization Wrap, which includes an inner sheet of wet laid paper (cellulose) and a separate outer sheet of spunlaced or hydroentangled pulp/polyester. The inner and outer layers are provided in a stack of loose, unattached sheets in which the inner and outer sheets are alternated.
Whatever the material is that is being used as sterile wrap, it should be noted that when wrapping two sheets at the same time, it is important that the wrapping materials provide good barrier properties to maintain package sterility and good strength properties so that tearing or other forms of breaching are held to a minimum. If the outer and inner sheets of the double wrap are to have different properties, then it is important that the system be visually identifiable so that the user can determine which wrapper is the outer sheet and which wrapper is the inner sheet. Consequently, there is a need for a new sterilization wrap system that actually reduces the time for packaging and opening and delivers outer and inner sheet engineered performance in a simple identifiable and easy to use fashion. Such attributes are provided by the present invention as will become more apparent upon a further review of the following specification, claims and drawings.
Disclosed herein is a single step sterilization wrap system for wrapping items in packages which are to be sterilized and maintained in a sterilized condition until use such as surgical instruments for hospital operating room use. A large number of such items are currently wrapped by two separate sheets of sterilization wrap. The most common method of wrapping such items is called double, sequential wrapping wherein an item is wrapped in a first piece of sterilization wrap with the loose ends being taped shut. Next, a second and separate sheet of sterilization wrap is used to wrap the item a second time. Once the second sheet of wrap has been wrapped around the item, the loose ends of the second sheet are taped closed and the wrapped item is sent through a sterilization process. After the wrapped item has been sterilized, it is normally placed in storage until actual use at which time the wrapped and sterilized package is removed from storage and transported to the operating room where the sterile wrap is removed and the items are subsequently used. A second and less commonly used method of wrapping is called the simultaneous wrapping wherein two sheets of sterilization wrap are placed one on top of the other, aligned and then the two sheets are wrapped about the item to be sterilized at the same time. After wrapping is complete, the loose ends are taped shut and the item is sent through the same sterilization process as described above.
The present invention provides an improved means for simultaneously wrapping and unwrapping items which must be sterilized prior to use. This is accomplished by bonding or joining two separate sheets of sterilization wrap together at one or more locations to create a single step system wherein the separate sheets are prealigned and joined to one another to facilitate the wrapping process as well as the unwrapping process. As a result, the amount of time needed to wrap and unwrap an item is decreased and the ease of wrapping is improved. In addition, each of the individual sheets of the single step sterilization wrap system can be specifically engineered or designed to impart special or different features to the overall system.
The single step sterilization wrap system includes an outer wrap made from a first sterilization sheet which is superposed on an inner wrap made from a second sterilization sheet with each of the sheets being independent of one another and joined to one another at one or more bond sites. The individual inner and outer wraps can be made from a variety of sterilization materials including fibrous materials such as nonwovens and wovens. The sterilization wrap system has a first exterior surface and a second exterior surface formed by the opposed sides of the system with each of the surfaces having respective surface area and wherein the bond sites joining the inner and outer wraps together occupy no more than 50% of the surface area of either the first or second exterior surfaces of the sterilization wrap system. The inner and outer wraps can be joined to one another in a variety of bonding patterns including both long continuous seams and point bonding. If desired, the sterilization wrap system can define a first zone and a second zone with the first zone having a greater number of the bond sites than the second zone and wherein the second zone is surrounded by the first zone so that the sterilization wrap system has an area of low density bonding surrounded by an area of higher density bonding.
Each of the individual sheets can be designed to have particular properties which may be the same or different from the other sheet of the single step sterilization wrap system of the present invention. For example, the outer wrap can be made stronger than the inner wrap as indicated by the outer wrap having a greater grab tensile strength as compared to the inner wrap. In addition, the barrier properties of the inner wrap can be fortified to create a better means of filtering bacteria than the outer wrap.
The inner wrap and outer wrap can both be made from nonwoven laminates such as spunbonded/meltblown/spunbonded laminates wherein the inner meltblown layer provides barrier properties and the outer spunbonded layers provides strength. By using a heavier basis weight meltblown layer in the inner wrap as compared to the outer wrap, the inner wrap will have a better barrier property than the outer wrap in which case the inner wrap will have a lower dry spore penetration rate than the outer wrap and a greater bacterial filtration efficiency than the outer wrap. Conversely, the meltblown layer of the inner wrap can be decreased to such an extent that the bacterial filtration efficiency of the inner wrap is less than the outer wrap. Furthermore, the strength of the inner and outer wraps can be varied by varying the basis weight and the types of polymers being used to form the fibers which make up the individual layers of the respective laminates. As a result, a sterilization wrap system can be designed wherein the peak energy of the outer wrap is greater than the inner wrap.
In situations where the inner wrap has different design properties than the outer wrap, it is important that the end user be able to determine which of the two wraps (inner or outer) should be placed adjacent the item being wrapped and subsequently sterilized. To this end, the inner and outer wraps can be designed so as to be visually distinct from another as by printing or other indicia as well as the use of different colors or shades with respect to the individual sheets of sterilization wrap.